In the sentences extracted from financial agreements in U.S. SEC filings, identify the named entities that represent a person ('PER'), an organization ('ORG'), or a location ('LOC'). The required answer format is: 'entity name, entity type'.
Text: " Dollars ," " dollars " and "$" each mean lawful money of the United States .
Answer:
United States, LOC
O O O O O O O O O O O O O O B-LOC I-LOC O
" Dollars ," " dollars " and "$" each mean lawful money of the United States .